1. Field of the Invention
This invention relates to the filtering and detection of light. Specifically, this invention relates to a system and method for enhancing, filtering and sensing light from various sources.
2. Description of Related Art
Optical sensors are essential to performing characterizations of light in many fields. These optical sensors allow for discrimination of light and allow for characterization of an emitting substance based on atomic absorption and emmision lines. However, many of these sensors often suffer from low signal-to-noise ratios, due to low-power optical signals combined with high levels of optical background noise.
Making optical sensors more practical requires increasing the signal-to-noise ratio to provide a detectable signal. This requires either a mechanism to increase the signal or decrease the noise. Generally, optical filters are used, which exhibit a 50% energy loss and are generally broadband.
Miniature optical detectors are currently fabricated using standard silicon processing technology. Examples include semiconductor pn junctions used for optical interconnects and computer chips. Often, these detectors use an optical fiber, so that the radiation is transmitted to a remote detector via the fiber. Such sources increase the optical noise of detection and, thus with increasing detector separation, the signal is generally decreased, and the system complexity is increased, due to additional components.
An additional problem with the prior art is that their systems and methods fail to discriminate between different wavelengths. Each source is characterized by different emission spectrum and reliable analysis of such samples requires wavelength discrimination. Additional filtering components increase costs and may introduce undesirable, thermo-mechanical properties, especially in hostile environments or configurations, requiring miniaturization.
Thus, there is a need in the prior art for means for shielding sensing materials from all but a small wavelength range of radiation. There is also a need for a filtering mechanism to filter all but a few wavelengths of impinging light and that can be easily varied.